Preservation of olfaction in anterior craniofacial approaches.

Through the combined efforts of neurosurgeons, head and neck surgeons, and craniofacial surgeons, the standard transbasal approach to the frontal fossa has been modified to include removal of the orbital roofs, nasion, and ethmoid sinuses. This approach has been combined further with facial disassembly procedures to provide extensive midline exposure to the midface and clival region. Extended frontal approaches, however, necessitate removal of the crista galli and sectioning of the olfactory rootlets with the associated risk of anosmia, cerebrospinal fluid (CSF) leak, and the need for complex reconstruction of the frontal floor. To avoid these problems, the authors have modified the technique of handling the cribriform plate to preserve the olfactory unit. Circumferential osteotomy cuts are made around the cribriform plate to allow an en bloc removal with its attachment to both the dura and underlying mucosa. Opening of the dura is avoided and the cribriform bone is used to reconstruct the floor. Four patients underwent this approach, for treatment of an angiofibroma in three and a fibrosarcoma in one. The mean follow-up period was 7 months. No patients developed a CSF leak, and within 8 weeks olfaction had returned in all patients. There was no other associated morbidity. These data suggest that this modification of the transbasilar approach can alleviate extensive reconstructive procedures and CSF leaks while preserving olfaction.